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The rolls are classified into two types; one is a single-solid type, and the other is a shrink-fitted construction type consisting of a sleeve and a shaft. The bimetallic work rolls are widely used in the roughing stands of hot rolling stand mills. Regarding a shrink-fitted construction type, the interfacial slip sometimes appears between the shaft and the shrink-fitted sleeve. This interfacial slip can be regarded as the relative displacement between the sleeve and the shaft. In this paper, the stress due to the interfacial slip is studied because the stress may cause the sleeve fracture. It is found that the stress in the shrink-fitted surface is slightly decreased with increasing number of rotations $n$. Therefore, the stress obtained by the simulation at $n=2$ can be used to estimate the fatigue strength.

In this study, tempering effect on the residual stress is studied after uniform heating–quenching and nonuniform heating–quenching for bimetallic work roll. Results for uniform heating treatment showed that the maximum stress at the center decreases by 68% from 396 MPa to 126 MPa after the first and second tempering. Results for nonuniform heating treatment showed that the maximum stress at the center decreases by 47% from 309 MPa to 165 MPa after the first and second tempering. It may be concluded that nonuniform heating–quenching and tempering are useful for reducing the central tensile stress preventing cracks at the roll surface.

The rolls are classified into two types; one is a single-solid type, and the other is a shrink-fitted construction type consisting of a sleeve and a shaft. The bimetallic work rolls are widely used in the roughing stands of hot rolling stand mills. Regarding a shrink-fitted construction type, the interfacial slip sometimes appears between the shaft and the shrink-fitted sleeve. This interfacial slip can be regarded as the relative displacement between the sleeve and the shaft. In this paper, the stress due to the interfacial slip is studied because the stress may cause the sleeve fracture. It is found that the stress in the shrink-fitted surface is slightly decreased with increasing number of rotations n. Therefore, the stress obtained by the simulation at n = 2 can be used to estimate the fatigue strength.